code: def unpack_mat(matin):
      """Extract relevant entries from unstructred readmat."""
      data = matin["data"]
      grad = data[0][0]["grad"]
      label = list()
      coil_label = list()
      for ii in range(len(data[0][0]["label"])):
          label.append(str(data[0][0]["label"][ii][0][0]))
      for ii in range(len(grad[0][0]["label"])):
          coil_label.append(str(grad[0][0]["label"][ii][0][0]))
  
      matout = {
          "label": label,
          "trial": data["trial"][0][0][0][0],
          "coil_label": coil_label,
          "coil_pos": grad[0][0]["coilpos"],
          "coil_ori": grad[0][0]["coilori"],
      }
      return matout
  
file_path: mne-python/mne/io/fil/tests/test_fil.py
imports: import shutil
  from os import remove
  import pytest
  import scipy.io
  from numpy import array, empty, isnan
  from numpy.testing import assert_array_almost_equal, assert_array_equal
  from mne import pick_types
  from mne.datasets import testing
  from mne.io import read_raw_fil
  from mne.io.fil.sensors import _get_pos_units
label_desc: Use image node_id 1 for calling a global function with example usage: unpack_mat(matin) and returns: matout